Perhaps the biggest challenge David Goulak faced during the second day of Boys 16 singles competition at 114th Ojai Valley Tennis Tournament on Friday was the five-hour wait between his two matches. The Oak Park resident won both, but not without a few tense moments in his second one.

Goulak, seeded No. 3, needed barely an hour to rout Riku Hashiyada of Irvine 6-1, 6-2 in his morning round-of-16 match at Nordhoff High, a performance Goulak admitted later in the day was near-perfect. His afternoon quarterfinal required a lot more effort, but Goulak held tough in the latter stages and defeated No. 5 seed Svyatoslav Shainyan of Ojai 6-3, 5-7, 6-4.

"In my morning match I played a decent player, but I just played amazing," Goulak said. "There was nothing he could do."

Coming back later in the afternoon, Goulak got off to another fast start, breaking Shainyan's serve in the first game en route to capturing the opening set 6-3. But there would be no quick victory this time.

Shainyan, who trains at the Weil Academy, fell behind a service break in the second set and was two games from defeat before rallying and sending the match to a final set.

The two players held the first five games of the third set before Goulak broke for a 4-2 lead, earning that break after outlasting Shainyan during a grueling rally that lasted more than 20 strokes. Leading 5-3, Goulak was unable to hold when serving for the match, but broke Shainyan with a forehand overhead at the net in the next game to clinch his victory.

Goulak was pleased he was able to finish strong, as well as stick to his game plan. That strategy, using his forehand to put Shainyan on the defensive and come to net, was a successful tactic early in the match and in the deciding set.

"He started playing better, stopped missing balls and I just stopped coming to the net," said Goulak in how Shainyan fought his way back in to the match. "That's how I was winning."

Goulak will play in the Boys 16 semifinals Saturday morning at Libbey Park against No. 8 seed Ethan Young-Smith of the Weil Academy. Joining Goulak in the semifinals is No. 2 seed Brandon Lam of Westlake Village, who will play No. 7 seed Humberto Lopez of National City.

Lam also needed three sets to win his quarterfinal, 4-6, 6-2, 6-3 over No. 6 seed Kento Perera of Santa Barbara. It was Lam's third straight three-set victory in two days.

"I'm exhausted, but I'm glad I got through it," Lam said. "After the first set I was able to get my head together and just started making my shots and playing the way I know how to play."

A few hours earlier Lam survived a hard-fought, round-of-16 battle against No. 9 seed Derek Chen of San Gabriel, 7-6, 6-7, 6-1. Lam squandered three match points in the 12th game of the second set — which he eventually lost 14-12 in the tiebreak — but then rolled in the third set.

Among other Ventura County players on Friday, No. 1 seed Annette Goulak of Oak Park and No. 2 seed Dominique Schaefer of Ventura each advanced to the semifinals in Girls 16 singles at Villanova Prep. Goulak only had to take the court once. After her round-of-16 opponent was injured and unable to play, Goulak won her quarterfinal 6-3, 6-3 over Christie Wan of Rowland Heights.

Schaefer dropped only two games in winning both of her matches Friday. She will face No. 3 seed Hannah Lairmore of Mobile, Ala., in the semifinals Saturday morning at Thacher School. Goulak will play No. 7 seed Emily Maxfield of Murrieta, also at Thacher.

In Boys CIF singles, Ryan Shen of Newbury Park advanced to the semifinals with two victories at Thacher School. Shen lost just three games in his round-of-16 match, then defeated Riley Smith of Los Alamitos 7-6 (7), 6-4 in the quarterfinals. Shen faces No. 2 seed Austin Rapp of Pam Desert in the semifinals at Libbey Park on Saturday morning.